φιλη :p
ο τρόπος είναι αυτός
External Reset (Lollipop)
1. With the phone powered off, press and hold the Volume Down button and the Power button at the same time until the device turns on. You will see the word "Start" with an arrow around it.
2. Press the Volume Down button twice to highlight "Recovery mode"
3. Press the Power button to restart into Recovery mode. You'll see an image of an Android robot with a red exclamation mark and the words "No command."
4. While holding down the Power button, press the Volume Up button.
5. Use the volume buttons to scroll to "wipe data/factory reset" and press the Power button to select it.
6. Scroll down to "Yes - erase all user data" and press the Power button to select it.
Από Recovery κάνεις επίσης Wipe cache και αν υπάρχει, Wipe Dalvik cache.